| "... we have to give them the proof that the changes they make will make a difference." Professor Ken Potter |
Top row, from left: Matt Robertsen, grad student, geography; Ken Bradbury, Wis. Geologic and Natural History Survey; Richard Lathrop, Dept. of Natural Resources; Prof. Joy Zedler, botany and UW Arboretum; Prof. Ken Potter, CEE; Kristin Anderson, grad student, geology and geophysics. Middle row: Dawn Chapel, grad student, geology and geophysics; Prof. Jean Bahr, geology and geophysics; Suzanne Hoehne, grad student, CEE. Front row: Laura Parent, grad student, geology and geophysics; Chip Hankley, Wis. Geological and Natural History Survey; Jeff Steurer, U.S. Geological Survey. |
Wild turkey, woodcock and snipe share the deep cold springs, marsh and upland and lowland woods of Pheasant Branch Conservancy with thousands of people whose homes surround the preserve. The area's beauty draws people to its borders. Ironically, the very qualities that draw people to the watershed are threatened because the development sheds too much water.
Streets, roofs, driveways and compacted soil do not allow water to percolate down through the earth's natural filter to the groundwater. Instead, rain runs off these surfaces and into the preserve, eroding channels and driving increasing amounts of sediment into the marsh, river and lakes. That, combined with pumping groundwater to serve the community, results in diminished groundwater levels in the wetlands and reduced discharge of high quality groundwater to springs, streams and lakes.
Civil and Environmental Engineering Professor Kenneth Potter and Wisconsin Department of Natural Resources Limnologist Richard Lathrop are co-principal investigators of a multidisciplinary study sponsored by the Environmental Protection Agency. The study seeks to develop models and find methods to minimize the hydrologic and ecological impacts of urbanization.
In the case of Pheasant Branch, the team is investigating what would happen if traditional urbanization continues to spread throughout the watershed as compared to urbanization requiring 'low impact' development practices.
In addition to developing methods and models, the team is taking into account social ramifications. Ultimately, changing development practices will mean asking property owners, developers and others to change their behavior.
"That's where the social science is going to be so important," says Potter. "We're going to have to get people to understand the problem and figure out how to implement solutions. I believe there are ways to have urban and suburban development without significantly impacting the streams in the area. This will require that we mitigate groundwater loss that results from pumping and the construction of impervious surfaces. But it is not enough to come up with scientific findings or engineering solutions. To be effective, you have to understand how development occurs and how development decisions are made and then figure out how changes might be made. It's tricky."
The North Fork of Pheasant Branch is an excellent study site, but it is by no means the only candidate for this type of research. The project results will hold meaning for watersheds across Wisconsin and the United States.
"This is much more than a planning exercise for Pheasant Branch. This is something that can have regional and national implications," says Lathrop. "We're really looking at the whole urbanization water resources problem. We want to put as much of the water as we can back into the ground and we want to decrease the runoff peak and volume as much as possible. It's a multifaceted approach."
Some approaches to curtailing runoff could involve narrower streets and new curb designs that allow water into the soil rather than into the storm sewer. Other approaches might involve rain gardens. Rain gardens can include a variety of plants and landscaping material and are designed to allow water from roofs and other surfaces to be absorbed by plants and soil. Potter says early indications are that committing space for a rain garden equivalent to 10 percent of a parcel's impervious surfaces may be enough to mitigate the runoff problems generated on that land.
"We're working on models to quantify this so that we can say 'these are the practices you need and what they will cost,'" says Potter. "The cost of many of these new practices is less than putting in storm sewers so I think developers are going to like it. Eventually we'd like to see some state leadership in this area. Stormwater is becoming a big issue. Developers could actually lead the way, but first we have to give them the proof that the changes they make will make a difference."
--By Jim Beal--
| For further information, please contact: |
Kenneth W. Potter, 608/262-0040
kwpotter@facstaff.wisc.edu
Copyright 2001 The Board of Regents of the University of Wisconsin System
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Date last modified: Thursday, 31-May-2001 09:06:25 CDT
Date created: 31-May-2001
